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Tesla Motors Announces a New Home Battery

offgridquest.com

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Re: Tesla Motors Announces a New Home Battery

#111

Post by shillster »

shiggerino wrote: post #80
headShrinker wrote: post #60

Earlier quoted context omitted.

Also many municipalities don't allow battery 'grid-tie' with the option of 'off the grid' living. For example, Connecticut has laws which don't allow houses to have batteries that would allow a house to be self sustaining and have a connection to the grid. This is because if you have batteries which cause a back flow during a power outage to the power station, an electrical worker could get shocked down the road. The…

Any reasonable grid company should not only not prohibit this, but welcome it and pay for energy people feed back into it. I can call mine any day and have a bi-directional meter put in so I can charge for it, should I ever choose to install solar panels.

In some states, it is required by law that the power company pay for home generated electricity that is fed back into the grid.

Re: Tesla Motors Announces a New Home Battery

#112

Post by jacquesm »

quarterwave wrote: post #57

I have home back-up power based on an inverter charging a lead-acid battery (located in a sheltered area outside the home), which costs about $100/kWh. Usage is about 1-2 hours discharge per day. No matter how well serviced, I've found these batteries don't last beyond four years. Hence I'd pay even $400/kWh for a well-engineered deep-cycle battery that is safe, maintenance-free, and will last at least 10 years. Excl…

> No matter how well serviced, I've found these batteries don't last beyond four years.

Wow, that's really short, especially with such a shallow discharge pattern.

Re: Tesla Motors Announces a New Home Battery

#113

Post by maxerickson »

lsaferite wrote: post #81
cjslep wrote: post #66

Earlier quoted context omitted.

"There ain't no such thing as a free lunch" from Heinlein's The Moon Is A Harsh Mistress , a highly recommended read.

Oh, I already looked it up. :) I was just realizing that it's not a hard problem to solve and sites could easily automate this, so they should. I guess you could argue that the browser could solve it as well. Or people could just write it out instead. :o

It's the kind of problem extension apis are really good for. I found this one:

http://abbrex.com/

Re: Tesla Motors Announces a New Home Battery

#114

Post by IgorPartola »

jacquesm wrote: post #59

It's very hard to beat lead-acid on: - $/Wh - number of cycles - ability to be recycled at eol - loss of capacity over the lifetime of the battery (or beyond!) - safety It is easy to beat on - power density - weight - maintenance - mechanical stability (especially for fluid based cells) - installation cost (lead/acid requires a sealed enclosure venting to the outside to get rid of free oxygen and hydrogen) The same b…

Energy density is a big one. To store 5 kW * 24 hours (barely enough to power my house's essentials), I would need 286 of these (http://www.amazon.com/VMAX857-Battery-Performance-minnkota-t...). They are not small. Also, that would cost me nearly $32,000 in just batteries.

My ideal setup for this would be something like 20 kW * 7 days. That would fill my basement pretty easily.

Re: Tesla Motors Announces a New Home Battery

#115

Post by IgorPartola »

headShrinker wrote: post #60
brudgers wrote: post #23

So, where does lithium come from? It comes from the Earth, of course, but it doesn't require strip mining or blowing the tops off mountains like other resources do...most often, lithium is found in briny underground ponds. The liquid is pumped out and left to dry in the sun. TANSTAAFL https://duckduckgo.com/?q=lithium+pond+photos&iax=1&ia=image... Mining is mining. There isn't a "green" form. Tearing holes in the ear…

Also many municipalities don't allow battery 'grid-tie' with the option of 'off the grid' living. For example, Connecticut has laws which don't allow houses to have batteries that would allow a house to be self sustaining and have a connection to the grid. This is because if you have batteries which cause a back flow during a power outage to the power station, an electrical worker could get shocked down the road. The…

Living in CT, is my gas generator considered a battery?

Re: Tesla Motors Announces a New Home Battery

#116

Post by msandford »

engendered wrote: post #97
headShrinker wrote: post #60

Earlier quoted context omitted.

Also many municipalities don't allow battery 'grid-tie' with the option of 'off the grid' living. For example, Connecticut has laws which don't allow houses to have batteries that would allow a house to be self sustaining and have a connection to the grid. This is because if you have batteries which cause a back flow during a power outage to the power station, an electrical worker could get shocked down the road. The…

>you can't even live 'off the grid' in a grid tied system I can't find any references for your stated claim about Connecticut, however it seems deeply illogical given that a generator (which surely aren't banned), solar panels, wind, etc, all have the potential of feeding energy back to the grid in an outage. Which is why there are regulations and home inspections and all of that, to ensure that the appropriate safet…

> where some users are trying to game the system by charging a big battery array during low cost hours, and then "selling" it back to the grid during peak hours (at inflated, subsidized prices).

The idea that a utility wants a heads-I-win-tails-you-lose kind of situation is annoying at best and downright infuriating at worst. If they're willing to sell power for $X now and willing to buy it later for $Y, what does it matter the method? I mean, there are people working on grid-scale storage batteries to do precisely that because utilities desperately NEED additional peak capacity when it's a hot day and everyone's A/C is on in the late afternoon. Why would it be OK for the UTILITY to utilize grid storage, but not an INDIVIDUAL?

http://en.wikipedia.org/wiki/Grid_energy_storage

Re: Tesla Motors Announces a New Home Battery

#117

Post by jacquesm »

IgorPartola wrote: post #114
jacquesm wrote: post #59

It's very hard to beat lead-acid on: - $/Wh - number of cycles - ability to be recycled at eol - loss of capacity over the lifetime of the battery (or beyond!) - safety It is easy to beat on - power density - weight - maintenance - mechanical stability (especially for fluid based cells) - installation cost (lead/acid requires a sealed enclosure venting to the outside to get rid of free oxygen and hydrogen) The same b…

Energy density is a big one. To store 5 kW * 24 hours (barely enough to power my house's essentials), I would need 286 of these ( http://www.amazon.com/VMAX857-Battery-Performance-minnkota-t... ). They are not small. Also, that would cost me nearly $32,000 in just batteries. My ideal setup for this would be something like 20 kW * 7 days. That would fill my basement pretty easily.

That's a very expensive battery for the given capacity. If you want to be efficient check out the gel batteries used to power golf carts and forklifts. You'll need 24 2V cells if you want to do this efficiently both from a cost perspective as well as to reduce line losses between batteries and inverters. (24 and 12V are really not adequate for larger power installations).

Re: Tesla Motors Announces a New Home Battery

#119

Post by jacquesm »

brudgers wrote: post #105
headShrinker wrote: post #60

Earlier quoted context omitted.

Also many municipalities don't allow battery 'grid-tie' with the option of 'off the grid' living. For example, Connecticut has laws which don't allow houses to have batteries that would allow a house to be self sustaining and have a connection to the grid. This is because if you have batteries which cause a back flow during a power outage to the power station, an electrical worker could get shocked down the road. The…

Such regulations provide several types of protection to the public commons. Another group of people who are protected are firefighters. In a typical residential installation the power meter also serves as the service disconnect. Response protocols include pulling the meter before many other life saving and property preserving operations. Live equipment and conductors operating from a second source downstream of the m…

And last but not least: when disconnected solar panels are 'open circuit' and the voltages will rise very rapidly. You can arc-weld with two fully illuminated 48V panels in parallel.

Re: Tesla Motors Announces a New Home Battery

#120

Post by IgorPartola »

jacquesm wrote: post #117
IgorPartola wrote: post #114

Earlier quoted context omitted.

Energy density is a big one. To store 5 kW * 24 hours (barely enough to power my house's essentials), I would need 286 of these ( http://www.amazon.com/VMAX857-Battery-Performance-minnkota-t... ). They are not small. Also, that would cost me nearly $32,000 in just batteries. My ideal setup for this would be something like 20 kW * 7 days. That would fill my basement pretty easily.

That's a very expensive battery for the given capacity. If you want to be efficient check out the gel batteries used to power golf carts and forklifts. You'll need 24 2V cells if you want to do this efficiently both from a cost perspective as well as to reduce line losses between batteries and inverters. (24 and 12V are really not adequate for larger power installations).

Such as these? http://www.batterystuff.com/batteries/golf-cart-products/

I don't really see orders of magnitude jumps in power/$. Or am I looking for the wrong thing?

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